Status of the TMT site evaluation process

The Thirty Meter Telescope (TMT) is currently acquiring site characterization data at ve candidate sites. The site testing equipment includes instruments for measuring the seeing and seeing proles, meteorological conditions, cloudiness, precipitable water vapor, etc. All site testing equipment and data have gone through extensive calibrations and verications in order to assure that a reliable and quantitative comparison between the candidate sites will be possible. Here, we present an update on the status of the site selection work, the equipment characterizations and the resulting accuracies of our site selection data.